Muslim
dynasties were soon established and subsequent empires such as
those of the Abbasids, Almoravids, Seljuk
Turks, Mughals in India and
Safavids in Persia and Ottomans were among the largest and most
powerful in the world. The Islamic world was composed of
numerous sophisticated centers of culture and science with
far-reaching mercantile networks, travelers, scientists,
astronomers, mathematicians, doctors and philosophers, all of whom contributed to
the Golden Age of Islam.

The
activities of this quasi-political early ummah
resulted in the spread of Islam as far from Mecca as China and Indonesia, the latter containing the world's largest Muslim
population. Today there are between 1.1 billion and
1.8 billion Muslims, making Islam the second-largest religion in the
world.

Note on historiography

Although Islamic history has been studied extensively, the early
years of expansions and their nature has remained a poorly studied
field in relation to its social, historical, affective or
psychological aspects according to some historians. The
conceptualization is dominated by two stereotypes; the first
popularized and captured by Gibbon in
the Decline and
Fall of the Roman Empire is of a fanatical Arab horseman riding forth from the desert with a
sword in one hand and the Qur'an in the other offering victims a choice between
one of the two, however such "old notions of forced conversions have been abandoned, at
least in scholarly literature." The other image is one of an
interfaith, interracial utopia where different races and peoples
lived together in harmony. This has also been discredited for more
shaded and complex views, such as an acculturation of Arab-Islamic
social norms and language, or a process of dialog between the
monotheisticArabs
during the Muslim conquests with
other faith traditions.

Phase I: The Early Caliphs and Umayyads(610-750)

This was the time of the life of Prophet Muhammad and his early
successors, the four rightly-guidedcaliphs, as well as the dynasty of the
Umayyad Caliphs (661-750).

In the first century the establishment of Islam upon the Arabian peninsula and the subsequent rapid
expansion of the Arab Empire during the
Muslim conquests, resulted in the
formation of an empire surpassed by none before. For the subjects
of this new empire, formerly subjects of the greatly reduced
Byzantine, and obliterated Sassanid, Empires, not much changed in
practice. The objective of the conquests was more than anything of
a practical nature, as fertile land and water were scarce in the
Arabian peninsula. A real Islamization therefore only came about in
the subsequent centuries.

Ira Lapidus distinguishes between two
separate strands of converts of the time: one is animists and
polytheists of tribal societies of the Arabian peninsula and the
Fertile crescent; the other one is
the monotheistic populations of the Middle Eastern agrarian and
urbanized societies.

For the polytheistic and pagan societies, apart from the religious
and spiritual reasons each individual may have had, conversion to
Islam "represented the response of a tribal, pastoral population to
the need for a larger framework for political and economic
integration, a more stable state, and a more imaginative and
encompassing moral vision to cope with the problems of a tumultuous
society." In contrast, for sedentary and often already monotheistic
societies, "Islam was substituted for a Byzantine or Sassanian
political identity and for a Christian, Jewish or Zoroastrian
religious affiliation." Conversion initially was neither required
nor necessarily wished for: "(The Arab conquerors) did not require
the conversion as much as the subordination of non-Muslim peoples.
At the outset, they were hostile to conversions because new Muslims
diluted the economic and status advantages of the Arabs."

Only in subsequent centuries, with the development of the religious
doctrine of Islam and with that the understanding of the Muslim
ummah, did mass conversion take place. The new
understanding by the religious and political leadership in many
cases led to a weakening or breakdown of the social and religious
structures of parallel religious communities such as Christians and
Jews.

The caliphs of the Umayyad dynasty established the first schools
inside the empire, called madrasas,
which taught the Arabic language and Islamic studies. They
furthermore began the ambitious project of building mosques across
the empire, many of which remain today as the most magnificent
mosques in the Islamic world, such as the Umayyad Mosque in
Damascus. At the end of the Umayyad period, less than 10% of the
people in Iran, Iraq, Syria, Egypt, Tunisia and Spain were Muslim.
Only on the Arabian peninsula was the proportion of Muslims among
the population even higher than this.

Phase II: The Abbasids (750-1258)

This was the time of the Abbasid Dynasty
(750-1258), the second great dynasty with the rulers carrying the
title of 'Caliph'.

Expansion ceased and the central disciplines of Islamic philosophy, theology,
law and mysticism
became more widespread and the gradual conversions of the
populations within the empire occurred. Significant conversions
also occurred beyond the extents of the empire such as that of the
Turkic tribes in Central Asia and peoples living in regions
south of the Sahara in Africa through contact with Muslim traders active in
the area and sufi missionaries.
In Africa
it spread along three routes, across the Sahara via trading towns
such as Timbuktu, up the
Nile Valley through the Sudan up to Uganda and across the
Red Sea and down East Africa
through settlements such as Mombasa and Zanzibar. These initial conversions were of a
flexible nature and only later were the societies forcibly purged
of their traditional influences.

The reasons why, by the end of the 10th century CE, a large part of
the population had converted to Islam are diverse. One of the
reasons may be that

"Islam had become more clearly defined, and the line
between Muslims and non-Muslims more sharply drawn. Muslims now
lived within an elaborated system of ritual, doctrine and law
clearly different from those of non-Muslims. (...) The status of
Christians, Jews and Zoroastrians was more precisely defined, and
in some ways it was inferior. They were regarded as the 'People of
the Book', those who possessed a revealed scripture, or 'People of
the Covenant', with whom compacts of protection had been made. In
general they were not forced to convert, but they suffered from
restrictions. They paid a special tax; they were not supposed to
wear certain colors; they could not marry Muslim
women;."

It should be pointed out that most of these laws were elaborations
of basic laws concerning non-Muslims (dhimmis) in the Quran. The
Quran does not give much detail about the right conduct with
non-Muslims, in principle recognizing the religions of the book and
demanding a separate tax for them.

American historian Ira Lapidus points
towards "interwoven terms of political and economic benefits and of
a sophisticated culture and religion" as appealing to the masses.
He writes that :

"The question of why people convert to Islam has always
generated intense feeling.

Earlier generations of European scholars believed that
conversions to Islam were made at the point of the sword, and that
conquered peoples were given the choice of conversion or
death.

It is now apparent that conversion by force, while not
unknown in Muslim countries, was, in fact, rare.

Muslim conquerors ordinarily wished to dominate rather
than convert, and most conversions to Islam were
voluntary.

(...) In most cases worldly and spiritual motives for
conversion blended together.

Moreover, conversion to Islam did not necessarily imply
a complete turning from an old to a totally new life.

While it entailed the acceptance of new religious
beliefs and membership in a new religious community, most converts
retained a deep attachment to the cultures and communities from
which they came."

The result of this, he points out, can be seen in the diversity of
Muslim societies today, with varying manifestations and practices
of Islam.

Conversion to Islam also came about as a result of the breakdown of
historically religiously organized societies: with the weakening of
many churches, for example, and the favoring of Islam and the
migration of substantial Muslim Turkish populations into the areas
of Anatolia and the Balkans, the "social and cultural relevance of
Islam" were enhanced and a large number of peoples were converted.
This worked better in some areas (Anatolia) and less in others
(e.g. the Balkans, where "the spread of Islam was limited by the
vitality of the Christian churches.")

Along with the religion of Islam, the Arabic language and Arab
customs spread throughout the empire. A sense of unity grew among
many though not all provinces, gradually forming the consciousness
of a broadly Arab-Islamic population: something which was
recognizably an Islamic world had emerged by the end of the 10th
century. Throughout this period, as well as in the following
centuries, divisions occurred between Persians and Arabs, and
Sunnis and Shiites, and unrest in provinces empowered local rulers
at times.

Conversion within the Empire: Umayyad Period vs. Abassid
Period

There are a number of historians who see the rule of the Umayyads
as responsible for setting up the "dhimmah" to increase taxes from
the dhimmis to benefit the Arab
Muslim community financially and to discourage conversion. Islam
was initially associated with the ethnic identity of the Arabs and
required formal association with an Arab tribe and the adoption of
the client status of mawali.
Governors lodged complaints with the caliph when he enacted laws
that made conversion easier, depriving the provinces of
revenues.

During the following Abbasid period an
enfranchisement was experienced by the mawali and a shift
was made in the political conception from that of a primarily Arab
empire to one of a Muslim empire and c. 930 a law was enacted that
required all bureaucrats of the empire to be Muslims. Both periods
were also marked by significant migrations of Arab tribes outwards
from the Arabian Peninsula into
the new territories.

Conversion within the Empire: Conversion
Curve

Richard Bulliet's "conversion curve"
shows a relatively low rate of conversion of non-Arab subjects
during the Arab centric Umayyad period of
10%, in contrast with estimates for the more politically
multicultural Abbasid period which saw the
Muslim population grow from approx. 40% in the mid 9th century to
close to 100% by the end of the 11th century.. This theory does not
explain the continuing existence of large minorities of Christians
in the Abbasid Period. Other estimates suggest that Muslims were
not a majority in Egypt until the mid-10th century and in the
Fertile Crescent until 1100. Syria may have had a Christian
majority within its modern borders until the Mongol Invasions of
the 13th century.

Phase III: Dissolution of the Abbasid Empire and its Reconquest
by the Ottomans (950-1450)

The
expansion of Islam continued in the wake of Turkic conquests of Asia Minor, the Balkans, and the
Indian subcontinent.The
earlier period also saw the acceleration in the rate of conversions
in the Muslim heartland while in the wake of the conquests the
newly conquered regions retained significant non-Muslim populations
in contrast to the regions where the boundaries of the Muslim world
contracted, such as Sicily and Al Andalus, where Muslim populations were expelled or forced
to Christianize in short
order. The latter period of this phase was marked by the
Mongol invasion and after an initial
period of persecution, the conversion of these conqueror's to
Islam.

Phase IV: Ottoman Empire: 13th Century - 1918

The Ottoman Empire defended its
frontiers initially against threats from several sides: the
Safavids on the Eastern side, the Byzantine Empire in the North which
vanished with the fall of Constantinople 1453, and the great
Catholic powers from the Mediterranean Sea: Spain, the Holy Roman
Empire, and Venice with its eastern Mediterranean colonies.

Later, the Ottoman Empire set on to conquer territories from these
rivals: Cyprus and other Greek islands (except Crete) were lost by
Venice to the Ottomans, and the latter conquered territory up to
the Danube basin as far as Hungary. Crete was conquered during the
17th century, but the Ottomans lost Hungary to the Holy Roman
Empire, and other parts of Eastern Europe, ending with the Treaty of Carlowitz (1699).

Phase V: (Post-Ottomans - present)

Islam has continued to spread through commerce, the activities of
Sufi missionaries, and migrations; especially
in Southeast Asia.

By region

Arabia

At
Medina, prophet Muhammad is said
to have received repeated embassies from Christian tribes.
His treatment of the Christian Arabs was distinctly more liberal
and courteous than that accorded by him to the calcinated Jews . He
looked on the latter as a potentially dangerous political menace,
while he regarded the former not only as subjects, but also as
friends and allies .

Asia

Soon after the death of prophet Muhammad,
all these provinces fell, one after the other, into the hands of
the Muslims, who threatened, for a while, the entire extinction of
Christianity in Western Asia.
Due
however to the tolerant attitude of the majority of the Umayyad, and the Abbasid
caliphs of Damascus and Baghdad
respectively, Christianity in the Muslim empire gradually began to
experience a new and unprecedented level of revival and
vigour.Nestorian and Jacobite theologians, philosophers, and men of
letters soon became the teachers of the conquering Arabs, and the
pioneers of Islamo-Arabic science, civilization, and learning.
Nestorian physicians became the attending physicians of the court,
and the Nestorian patriarch and his numerous bishops were regarded
in Asia as second to none in power and authority.

Under the Umayyad and Abbasid Caliphs, Christianity enjoyed, with
few exceptions, great freedom and respect throughout all the Muslim
Empire, as can be seen from the facts and data collected by
Assemani and Bar-Hebraeus, according to which many Nestorian
and Jacobite patriarchs from the seventh to the eleventh centuries
received diplomas, or firmans, of some sort from prophet Muhammad himself, from Umar,
Ali, Marwan, Al-Mansur, Harun
al-Rashid, Abu Ja'far, and
others. (Shedd, op. cit., 239-241; Assemani, De Catholicis
Nestorianis, 41-433 sqq.; Bar-Hebraeus, Chronicon Ecclesiasticum I,
309, 317, 319, 325; II, 465, 625; III, 307, 317, 229, 433, etc.;
and Thomas of Marga, op. cit., II, 123, note.)

Greater Syria

In
635Damascus surrendered, its inhabitants being promised
security for their lives, property, and churches, onpayment
of a poll tax. by 640
the conquest was virtually complete. The Arab garrisons were kept
apart in camps, andlife went on much as before. Conversion to Islam
had scarcely begun, apart from Arab tribes already settled in
Syria;except for the tribe of Ghassan, these
all became Muslim. Christians and Jews were treated with
toleration, andNestorian and Jacobite Christians had better treatment than
they had under Byzantium. The loyalty of
his new subjects was paramount to the success of Muslim rule in the
region, therefore excessive taxation or oppression was
avoided.

Like their Byzantine and late Sasanian predecessors, the Marwanid caliphs nominally ruled the various
religious communities but allowed the communities' own appointed or
elected officials to administer most internal affairs. Yet the
Marwanids also depended heavily on the help of non-Arab
administrative personnel and on administrative practices (e.g., a
set of government bureaus). As the conquests slowed and the
isolation of the fighters (muqatilah) became less
necessary, it became more and more difficult to keep Arabs
garrisoned. As the tribal links that had so dominated Umayyad
politics began to break down, the meaningfulness of tying non-Arab
converts to Arab tribes as clients was diluted; moreover, the
number of non-Muslims who wished to join the ummah was already
becoming too large for this process to work effectively.

Palestine

The Muslims arrived at Jerusalem around early November 636, and the Roman garrison withdrew into the fortified
city. For four months the siege continued, every day there was a
fierce assault. At last, when all further resistance washopeless,
the Patriarch
Patriarch Sophronius (who acted throughout as the head of the
Christian defenders) appeared on thewalls and demanded a conference
with Abu Ubaidah. He then proposed to
capitulate on fair and honorable terms; theChristians were to keep
their churches and sanctuaries, no one was to be forced to accept
Islam. Sophronius furtherinsisted that
these terms should be ratified by the caliph in person. CaliphUmar, then at Medina,
agreed to these terms andcame with a single camel to the walls of
Jerusalem. He signed the capitulation, then entered
the city with Sophronius"and courteously discoursed with the
patriarch concerning its religious antiquities" .

It is said that when the hour for his prayer came he was in the
Anastasis, but refused to say itthere, lest in future times the
Muslims should make that an excuse for breaking the treaty and
confiscating thechurch. The Mosque of Omar (Jami 'Saidna 'Omar),
opposite the doors of the Anastasis, with the tall minaret, is
shownas the place to which he retired for his prayer. Under the
Muslim the Christian population of Jerusalem in the firstperiod
enjoyed the usual toleration given to non-Muslim theists. The
pilgrimages went on as before.From that point, the rights of the
non-Muslims under Islamic territory were governed by the Pact of Umar,and Christians and Jews living in
the city were granted autonomy in exchange for a required poll tax (jizya).

The description of Arculf, a Frankish bishop who went on a
pilgrimage to the Holy Land in the seventh century,written down
from his account by Adamnan, monk of Iona (d. 704): "De locis
terrae sanctae", lib. III (P. L.,LXXXVIIl, 725 sq.), gives us a not
unpleasant picture of the conditions of Christians in Palestine in
the firstperiod of Muslim rule. The caliphs of Damascus (661-75O)
were enlightened and tolerant princes, on quite good termswith
their Christian subjects. Many Christians (e.g. St. John Damascene,
d. c. 754) held important offices at theircourt. The Abbaside
caliphs at Baghdad (753-1242), as long as they ruled Syria, were
also just and tolerant to theChristians. The famous Harun
Abu-Ja-'afar (Haroun al-Raschid,
786-809) sent the keys of the Holy Sepulchre toCharlemagne who built a hospice for Latin
pilgrims near the shrine.

During the Fatimid rule, Romans were attacking Syria. It was
inevitable that the Christians of Jerusalem should tryto help their
fellow-countrymen to reconquer the land that had been Roman and
Christian; inevitable, too, that theMuslims should punish such
attempts as high treason. In 969 the patriarch,
John VII, was put to death for treasonablecorrespondence with the
Romans; many other Christians suffered the same fate, and a number
of churches weredestroyed. The infamous Hakim
(Al-Hakim bi-amr-Allah, the sixth Egyptian Caliph, 996-1021, who
became the god ofthe Druze) determined to
destroy the Holy Sepulcher (In 1010). It was one of the causes of
the feeling thateventually brought about the First Crusade. It was rebuilt in 1048.

The caliphs go in the order of Abu Bakr,
then Umar, followed by Uthman, and Ali then his son Hassan, before
the Sunni Shia split.

Iraq, Persia, and Central Asia

It used to be argued that Zoroastrianism quickly collapsed in the wake
of the Islamic conquest of
Persia due to its intimate ties to the Sassanid state structure. Now however, more complex
processes are considered, in light of the more protracted time
frame attributed to the progression of the ancient Persian religion
to a minority; a progression that is more contiguous with the
trends of the late antiquity period.
These trends are the conversions from the state religion that had
already plagued the Zoroastrian authorities that continued after
the Arab conquest, coupled with the migration of Arab tribes into
the region during an extended period of time that stretched well
into the Abbassid reign.

While
there were cases such as the Sassanid army division at Hamra, that
converted en masse before pivotal battles such as the
Battle of
al-Qādisiyyah, conversion was fastest in the urban areas where Arab forces were garrisoned slowly leading to Zoroastrianism
becoming associated with rural areas.
Still at the end of the Umayyad period, the Muslim community was
only a minority in the region.

H.G. Rawlinson, in his book: Ancient and Medieval History of
India claims the first Arab Muslims settled on the Indian
coast in the last part of the 7th century AD. This fact is
corroborated, by J. Sturrock in his South Kanara and Madras
Districts Manuals, and also by Haridas Bhattacharya in
Cultural Heritage of India Vol.IV.The Arab
merchants and traders became the carriers of the new religion and
they propagated it wherever they went. It was however the
subsequent expansion of the Muslim conquest in
the Indian subcontinent over the next millennia that
established Islam in the region.

Considerable controversy exists both in scholarly and public
opinion about the conversions to Islam. Some Indian historians,
such as K.S.Lal,
suggest that some 80 million Hindus could
have been killed over the centuries, through the Islamic conquest
of the Indian subcontinent.
Embedded within this lies the concept of Islam as a foreign
imposition and Hinduism being a natural
condition of the natives who resisted, resulting the failure of the
project to Islamicize the Indian subcontinent and is highly
embroiled with the politics of the partition and communalism in India. These are typically
represented by the following schools of thought:

That the bulk of Muslims are descendants of migrants from the
Iranian plateau or Arabs.

Southeast Asia

Islam came to the Southeast Asia,
first by the way of Muslim traders along the main trade-route
between Asia and the Far East, then was
further spread by Sufi missionaries and finally consolidated by the
expansion of the territories of converted rulers and their
communities. The first communities arose in Northern
Sumatra (Aceh) and the
Malacca's remained a stronghold of Islam from where it was
propagated along the trade routes in the region. There is no
clear indication of when Islam first came to the region, the first
Muslim gravestone markings date to 1082.

When
Marco Polo visited the area in 1292 he
noted that the urban port state of Perlak
was Muslim, Chinese sources record the presence of a Muslim
delegation to the emperor from the Kingdom of
Samudra in 1282, other accounts provide instances of Muslim
communities present in the Melayu
Kingdom for the same time period while others record the
presence of Muslim Chinese traders from provinces such as Fujian.The
spread of Islam generally followed the trade routes east through
the primarily Buddhist region and a half
century later in the Malacca's we see the first dynasty arise in the form of the
Sultanate of Malacca at the far
end of the Archipelago form by the conversion of one Parameswara Dewa Shah into a Muslim and
the adoption of the name Muhammad Iskandar Shah after his marriage
to a daughter of the ruler of Pasai.

In 1380
Sufi missionaries carried Islam from here on to Mindanao.Java was the seat
of the primary kingdom of the region, the Majapahit Empire, which was ruled by a
Hindu dynasty. As commerce grew in the
region with the rest of the Muslim world, Islamic influence
extended to the court even as the empires political power waned and
so by the time Raja Kertawijaya converted in
1475 at the hands of Sufi Sheikh Rahmat, the
Sultanate was already of a Muslim character.

Another driving force for the change of the ruling class in the
region was the concept among the increasing Muslim communities of
the region that only the descendants of the Islamic prophetMuhammad (Sayyid) were fit to rule them causing the ruling
dynasties to attempt to forge such ties of kinship by marriage.
By the
time the colonial powers and their
missionaries arrived in the 17th
century the region up to New Guinea was overwhelmingly Muslim with animist minorities.

Some of the Mongolian tribes became Islamized. Following the brutal
Mongol invasion of
Central Asia under Hulagu Khan and
after the Battle of Baghdad
Mongol rule extended across the breadth of almost all Muslim lands
in Asia,and the caliphate was destroyed and
Islam was persecuted
by the Mongols and replaced by Buddhism
as the official religion of the land. In 1295 however, the new Khan
of the Ilkhanate, Ghazan converted to Islam and two decades later the
Golden Horde followed suit. The Mongols had been religiously and
culturally conquered, this absorption ushered in a new age of
Mongol-Islamic synthesis that shaped the further spread of Islam in
central Asia and the Indian
subcontinent.

Africa

North Africa

In
Egypt, the victorious Muslims granted religious freedom
to the Christian community in Alexandria, for example, and the Alexandrians quickly recalled
their exiled Monophysite patriarch to
rule over them, subject only to the ultimate political authority of
the conquerors. In such a fashion the city persisted as a
religious community under an Arab Muslim domination more welcome
and more tolerant than that of Byzantium.

Byzantine
rule was ended by the Arabs, who invaded Morocco in 682 in the course of their
drive to expand the power of Islam. Except for the Jews, the
inhabitants of Morocco, both Christian and pagan, 10 years later
they accepted the religion of their conquerors. Berber troops were used extensively by the
Arabs in their conquest of Spain, which began in 711.

No previous conqueror had tried to assimilate the Berbers, but the
Arabs quickly converted them and enlisted their aid in further
conquests. Without their help, for example, Andalusia could never
have been incorporated into the Islamicate state. At first only
Berbers nearer the coast were involved, but by the 11th century
Muslim affiliation had begun to spread far into the Sahara.

The Marwanid Maghrib illustrates a kind of
conversion more like that of the peninsular Arabs. After the defeat
of initial Berber resistance movements, the Arab conquerors of the
Maghrib quickly incorporated the Berber tribes en masse into the
Muslim community, turning them immediately to further conquests.
In 710 an
Arab–Berber army set out for the Iberian Peninsula under the leadership of Tariq ibn Ziyad.

Horn of Africa

The history of commercial and intellectual contact between the
inhabitants of the Somali coast and the Arabian Peninsula may help explain the
Somali people's connection with the Prophet Muhammad. Early on, a band of persecuted Muslims had, at the Prophet's urging, fled across the
Red
Sea into the Horn of
Africa. There, the Muslims were granted protection by
the Ethiopian negus (king). Islam may thus have been introduced into the Horn of
Africa well before the faith even took root in its place of
origin.

East Africa

On the
east coast of Africa, where Arab mariners had for many years
journeyed to trade, Arabs founded permanent colonies on the
offshore islands, especially on Zanzibar, in the 9th and 10th century. From there
Arab trade routes into the interior of Africa helped the slow
acceptance of Islam.In the 20th cent. Islam has gained more
converts in Africa than has Christianity, which labors under the
burden of identification with European imperialism.

West Africa

The spread of Islam in Africa began in the 7th to 9th century CE,
brought to North Africa initially under the Umayyad Dynasty. Extensive trade networks
throughout North and West Africa created a medium through which
Islam spread peacefully, initially through the merchant class. By
sharing a common religion and a common language (Arabic), traders showed greater willingness to trust,
and therefore invest, in one another.

Europe

Hispania /Al-Andalus

The history of Arab and Islamic rule in the Iberian peninsula is
probably one of the most studied periods of European history, but
the variety and quantity of writing has not escaped the prejudices
of the authors. For centuries after the Arab conquest, European
accounts of Arab rule in Iberia were negative, reflecting Christian
insecurities generated by the wave of Arab victories. European
points of view started changing with the Protestant Reformation,
which resulted in new descriptions of the period of Islamic rule in
Spain as a "golden age" (mostly as a reaction against Spain's
militant Roman Catholicism after 1500).

The tide of Arab expansion after 630 rolled through North Africa up
to Ceuta in present day Morocco. Their arrival coincided with a
period of political weakness in the three centuries old kingdom
established in the Iberian peninsula by the Germanic Visigoths, who
had taken over the region after seven centuries of Roman rule.
Seizing the opportunity, an Arab-led (but mostly Berber) army
invaded in 711, and by 720 had conquered almost all of the
peninsula. The Arab expansion pushed over the mountains into
southern France, and for a short period Arabs controlled the old
Visigothic province of Septimania (centered on present-day
Narbonne). The Arab Caliphate was pushed back by Charles Martel
(King of the Franks or French) at Poitiers, and Christian armies
started pushing southwards over the mountains, until Charlemagne
established in 801 the Spanish March (which stretched from
Barcelona to present day Navarre).

A major development in the history of Muslim Spain was the dynastic
change in 750 in the Arab Caliphate, when an Ummayad Prince escaped
the slaughter of his family in Damascus, fled to Cordoba in Spain,
and created a new Islamic state in the area. This was the start of
a distinctly Spanish Muslim society, where large Christian and
Jewish populations coexisted with an increasing percentage of
Muslims. There are many stories of descendants of Visigothic
chieftains and Roman counts whose families converted to Islam
during this period. The at-first small Muslim elite continued to
grow with converts, and with a few exceptions, rulers in Islamic
Spain allowed Christians and Jews the right specified in the Koran
to practice their own religions. While it was true that non Muslims
suffered from political and taxation inequities, the Jewish and
Christian people where allowed to practice their religions and
culture. The net result was, in those areas of Spain where Muslim
rule lasted the longest, the creation of a society that was mostly
Arabic-speaking because of the assimilation of native inhabitants,
a process in some ways similar to the assimilation many years later
of millions of immigrants to the United States into
English-speaking culture.

The Islamic state centered in Cordoba ended up splintering into
many smaller kingdoms (the so-called taifas). While Muslim Spain
was fragmenting, the Christian kingdoms grew larger and stronger,
and the balance of power shifted against the taifa kingdoms. The
last Muslim kingdom of Granada in the south fell to Christian
conquerors in 1492. In 1499, the remaining Muslim inhabitants were
ordered to convert or leave (at the same time the Jews were
expelled). Poorer Muslims (Moriscos) who
could not afford to leave ended up converting to Catholic
Christianity and hiding their Muslim practices, hiding from the
Spanish Inquisition, until their presence was finally
extinguished.

Balkans

In Balkan history writing the question of conversion to Islam was,
and still is, a highly charged political issue. It is intrinsically
linked to the issues of formation of national identities and rival
territorial claims of the Balkan states. The generally accepted
nationalist discourse of the current Balkan historiography defines
all forms of Islamization as results of the Ottoman government's
centrally organized policy of conversion or dawah. The truth is that islamization in each
Balkan country took place in the course of many centuries and its
nature and phase was determined not by the Ottoman government but
by the specific conditions of each locality. Ottoman conquests were
initially military and economic enterprises, and religious
conversions were not the their primary objective. True, the
statements surrounding victories all celebrated the incorporation
of territory into Muslim domains, but the actual Ottoman focus was
on taxation and making the realms productive, and a religious
campaign would have disrupted that economic objective.

Ottoman Islamic standards of toleration allowed for autonomous
"nations" (millets)
in the Empire, under their own personal law and under the rule of
their own religious leaders. As a result, vast areas of the Balkans
remained mostly Christian during the period of Ottoman domination.
In fact, the Eastern Orthodox Churches had a higher position in
Ottoman Empire, mainly because the Patriarch resided in Istanbul
and was an officer of the Ottoman Empire. In contrast, Roman
Catholics, while tolerated, were suspected with loyalties to a
foreign power (the Papacy). It is no surprise that the Roman
Catholic areas of Bosnia, Kosovo and northern Albania, ended up
with more substantial conversions to Islam. The defeat of the
Ottomans in 1699 by the Austrians resulted in their loss of Hungary
and present-day Croatia. The remaining Muslim converts in both
elected to leave "lands of unbelief" and moved to territory still
under the Ottomans. Around this point in time, new European ideas
of romantic nationalism started to seep into the Empire, and
provided the intellectual foundation for new nationalistic
ideologies and the reinforcement of the self-image of many
Christian groups as subjugated peoples.

One by one, the Balkan nationalities asserted their independence
from the Empire, and frequently the presence of members of the same
ethnicity who had converted to Islam presented a problem from the
point of view of the now dominant new national ideology, which
narrowly defined the nation as members of the local dominant
Orthodox Christian denomination. Thousand of Muslims chose to
leave, and in some cases were expelled, to what was left of the
Ottoman Empire. This demographic transition can be
illustrated by the decrease in the number of Mosques in Belgrade, from over 70 in 1750 (before Serbian independence
in 1815), to only three in 1850.

As an example of what most indigenous Muslims endured when the new
Christian nation-states emerged in the 19th century, peninsular and
Cretan Greeks, who saw themselves as Greek first and spoke the
Greek language, eventually were still forced to leave Greece. In
the long run, with the exception of Bosnia, Albania, and Kosovo,
the vast majority of descendants of Balkan converts to Islam
emigrated to Turkey and integrated themselves into Turkish
society.